A power semiconductor module used in a power converting device for driving a motor has a large heat value during operation. The heat generation occurs in power semiconductor elements such as transistor elements and diode elements mounted on the inside of the power semiconductor module. For this reason, in the conventional power converting device, a cooling structure such as a cooling fin or a cooling fan is provided on the outside of the power semiconductor module to perform heat dissipation and cooling of the power semiconductor module.
Patent Literature 1 discloses a technique in which internal uneven heat distribution and temperature gradient can be reduced, inductance component due to interconnect line between semiconductor elements can be reduced, and cooling can be performed efficiently depending on the conditions of heat generation of a power semiconductor element. In this technique, there is disclosed a power semiconductor module comprising a cooling substrate, and at least two power semiconductor elements mounted, respectively, on the front and rear of the substrate. The power semiconductor elements include an IGBT and a diode, the IGBT is mounted on the front or rear of the substrate, and the diode is mounted on the front or rear of the substrate at a position matching the mounting position of the IGBT while interposing the substrate.
Patent Literature 2 discloses a technique to reduce inductance in a semiconductor device which causes increase of overshooting voltage when switching, accompanying an element breakdown and an increase of power loss. In this technique, a part of wiring to bridge-connect semiconductor switches is made in lamination, and at least two DC terminal pairs, each connected to the part of the wiring, are disposed arranging the plus poles and the minus poles alternately on one side of the upper face of the square case of the semiconductor.